Yamaha YZ450F(D) Owner's Service Manual page 202

Fault code No.
Symptom
Fail-safe system
Diagnostic code No.
FI diagnostic tool display
Checking method
Item Item/components and probable cause
5 Applied voltage of throttle position sensor lead Measure the output voltage.
6 Defective throttle position sensor.
7 Malfunction in ECU.
15
Throttle position sensor signal is not received properly.
Able to start
Able to drive
D01
• 15–19° (Fully closed position)
• 95–101° (Fully opened position)
• Check with throttle valves fully closed.
• Check with throttle valves fully open.
FUEL INJECTION SYSTEM
Check or maintenance job
Refer to "CHECKING THE
THROTTLE POSITION SEN-
SOR".
Open circuit Applied voltage
item
Ground wire 5 V
open circuit
Output wire 0 V
open circuit
Power supply 0 V
wire open circuit
Execute the diagnostic mode (di-
agnostic code No. D01).
When throttle is fully closed: A
value of 15–19 is indicated.
When throttle is fully opened: A
value of 95–101 is indicated.
Displayed value is out of specifica-
tion → Replace.
Replace the ECU.
7-18
Checking method
Set the switch on the FI di-
agnostic tool sub-wire har-
ness to "ON", and then
check the fault code dis-
play.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 6.
Set the switch on the FI di-
agnostic tool sub-wire har-
ness to "ON", and then
check the fault code dis-
play.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 7.